A Possible Phase Transition in beta-pyrochlore Compounds
Strongly Correlated Electrons
2009-11-13 v1 Statistical Mechanics
Abstract
We investigate a lattice of interacting anharmonic oscillators by using a mean field theory and exact diagonalization. We construct an effective five-state hopping model with intersite repulsions as a model for beta-pyrochlore AOs_2O_6(A=K, Rb or Cs). We obtain the first order phase transition line from large to small oscillation amplitude phases as temperature decreases. We also discuss the possibility of a phase with local electric polarizations. Our theory can explain the origin of the mysterious first order transition in KOs_2O_6.
Cite
@article{arxiv.0809.0732,
title = {A Possible Phase Transition in beta-pyrochlore Compounds},
author = {Kazumasa Hattori and Hirokazu Tsunetsugu},
journal= {arXiv preprint arXiv:0809.0732},
year = {2009}
}
Comments
4 pages, 4 figures, submitted to J. Phys. Soc. Jpn